Hand drill



J. V. BORDEN Jan. 17, 1967 HAND DRILL Original Filed Nov. 17, 1958 INVENTOR JOHN L/ BORDEN ATTORNEYS United States Patent 2 Claims. (Cl. 279-102) This application is a division of my prior application,

Serial No. 774,345, filed November 17, 1958, now abandoned.

An object of one embodiment of this invention is in the provision of means to eject a drilling bur from a dental handpiece when the mechanism is not being used.

These and other objects of the invention will become more readily apparent from a consideration of the following detailed description of the invention taken in conjunction with the accompanying drawings in which:

FIGURE 1 is a longitudinal cross-section of a portion of a dental handpiece embodying one form of the present invention;

FIGURE 2 is a longitudinal cross-section of a portion of the handpiece of FIGURE 1 and taken on a plane at right angles to the plane of FIGURE 1, and;

FIGURE 3 is a cross-section taken on the line 33 of FIGURE 1.

Referring now to FIGS. 1, 2 and 3, there is shown an embodiment of this invention which is provided with a water supply means and incorporates a single unitary housing section. Referring particularly to FIG. 1, there is shown a handpiece which is comprised of three major sections; a handle 70, a housing 72 and a nozzle member 74. The housing 72 has at one end thereof a cavity defined by side walls 75. This cavity is adapted to receive the rotor assembly. The other end of the housing is a substantially solid block in which exhaust port 82, water bore 92, air bore 78, and the stem receiving bore 77, are drilled therein. A water tube 79, prefer-ably of brass, is inserted in 1mm 78 and extends to a point without the housing 72 for a short distance and re-enters the housing at a point 81 adjacent an orifice which directs the air against the rotor vanes '82 of rotor 84.

Air is delivered to the handpiece via tube 76 which is connected to tube 78 at a point 85. The rotor 84 is fixedly secured to a hollow shaft 86, and is rotated by air discharged from orifice [80.

I claim:

1. A bur extraction mechanism for use with a drill having an elongated straight handpiece housing, a fluid driven turbine axially positioned within the housing including a shaft having one end in alignment with an axial opening at one end of the housing, said shaft having an axial passage throughout its length and including means for frictionally receiving a bur at said one end, an elongated stem axially slidably mounted within said handpiece housing in alignment with said shaft and freely slidable in said passage for ejecting a bur, said stem including a transverse member movable in a longitudinal slot in said housing, and a ring shaped member encircling the exterior of the housing connected with said transverse member.

'2. The invention as defined in claim 1, wherein said means for receiving a bur includes a resilient sleeve positioned within said shaft.

References Cited by the Examiner UNITED STATES PATENTS 819,025 4/ 1906 Rich. 3,082,528 3/1963 Reid 279-103 FOREIGN PATENTS 17,024 1911 Great Britain.

ROBERT C. RIORDON, Primary Examiner.

LESTER M. SWINGLE, Examiner.

H. V. STAHLHUTH, Assistant Examiner, 

1. A BUR EXTRACTION MECHANISM FOR USE WITH A DRILL HAVING AN ELONGATED STRAIGHT HANDPIECE HOUSING, A FLUID DRIVEN TURBINE AXIALLY POSITIONED WITHIN THE HOUSING INCLUDING A SHAFT HAVING ONE END IN ALIGNMENT WITH AN AXIAL OPENING AT ONE END OF THE HOUSING, SAID SHAFT HAVING AN AXIAL PASSAGE THROUGHOUT ITS LENGTH AND INCLUDING MEANS FOR FRICTIONALLY RECEIVING A BUR AT SAID ONE END, AN ELONGATED STEM AXIALLY SLIDABLY MOUNTED WITHIN SAID HANDPIECE HOUSING IN ALIGNMENT WITH SAID SHAFT AND FREELY SLIDABLE IN SAID PASSAGE FOR EJECTING A BUR, SAID STEM INCLUDING A TRANSVERSE MEMBER MOVABLE IN A LONGITUDINAL SLOT IN SAID HOUSING, AND A RING SHAPED MEMBER ENCIRCLING THE EXTERIOR OF THE HOUSING CONNECTED WITH SAID TRANSVERSE MEMBER. 